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// Copyright (c) 2008, Massachusetts Institute of Technology              //
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////////////////////////////////////////////////////////////////////////////

#include "MaxLikelihoodSmoothing.h"
#include "KneserNeySmoothing.h"

namespace mitlm {

Smoothing *
Smoothing::Create(const char *smoothing) {
    if (strcmp(smoothing, "FixKN") == 0) {
        return new KneserNeySmoothing(1, false);
    } else if (strcmp(smoothing, "FixModKN") == 0) {
        return new KneserNeySmoothing(3, false);
    } else if (strncmp(smoothing, "FixKN", 5) == 0) {
        for (size_t i = 5; i < strlen(smoothing); ++i)
            if (!isdigit(smoothing[i])) return NULL;
        return new KneserNeySmoothing(atoi(&smoothing[5]), false);
    } else if (strcmp(smoothing, "KN") == 0) {
        return new KneserNeySmoothing(1, true);
    } else if (strcmp(smoothing, "ModKN") == 0) {
        return new KneserNeySmoothing(3, true);
    } else if (strncmp(smoothing, "KN", 2) == 0) {
        for (size_t i = 2; i < strlen(smoothing); ++i)
            if (!isdigit(smoothing[i])) return NULL;
        return new KneserNeySmoothing(atoi(&smoothing[2]), true);
    } else if (strcmp(smoothing, "ML") == 0) {
        return new MaxLikelihoodSmoothing();
    } else
        return NULL;
}

}
